/*
 * The contents of this web application are subject to the Mozilla Public License Version 
 * 1.1 (the "License"); you may not use this web application except in compliance with 
 * the License. You may obtain a copy of the License at http://www.mozilla.org/MPL/.
 * 
 * Software distributed under the License is distributed on an "AS IS" basis, 
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 
 * for the specific language governing rights and limitations under the License.
 * 
 * The Original Code is owned by and the Initial Developer of the Original Code is 
 * Composite A/S (Danish business reg.no. 21744409). All Rights Reserved
 * 
 * Section 11 of the License is EXPRESSLY amended to include a provision stating 
 * that any dispute, including but not limited to disputes related to the enforcement 
 * of the License, to which Composite A/S as owner of the Original Code, as Initial 
 * Developer or in any other role, becomes a part to shall be governed by Danish law 
 * and be initiated before the Copenhagen City Court ("K�benhavns Byret")            
 */

using System;
using System.Collections.Generic;
using System.Linq;
using Composite.C1Console.Elements;
using Composite.C1Console.Security;
using Composite.C1Console.Trees.Foundation;
using Composite.C1Console.Trees.Foundation.AttachmentPoints;


namespace Composite.C1Console.Trees
{
    /// <summary>
    /// This node is a virtual node represending the element that the tree is attached under.
    /// </summary>    
    internal class RootTreeNode : TreeNode
    {
        public RootTreeNode()
        {
            this.Id = StringConstants.RootNodeId;
        }

        private class AncestorMatch
        {
            public Type InterfaceType;
            public object KeyValue;
        }


        public override IEnumerable<EntityToken> GetEntityTokens(EntityToken childEntityToken, TreeNodeDynamicContext dynamicContext)
        {
            TreeSimpleElementEntityToken treeSimpleElementEntityToken = childEntityToken as TreeSimpleElementEntityToken;
            if (treeSimpleElementEntityToken != null)
            {
                yield return treeSimpleElementEntityToken.ParentEntityToken;
            }
            else
            {
                AncestorMatch ancestorFromFilter = GetAncestorFromParentFilter(dynamicContext);

                foreach (IAttachmentPoint attachmentPoint in this.Tree.AttachmentPoints)
                {
                    if(attachmentPoint is DynamicDataItemAttachmentPoint 
                        && ancestorFromFilter != null)
                    {
                        var dynamicAttachmentPoint = attachmentPoint as DynamicDataItemAttachmentPoint;

                        if (ancestorFromFilter.InterfaceType == dynamicAttachmentPoint.InterfaceType)
                        {
                            if (dynamicAttachmentPoint.KeyValue.Equals(ancestorFromFilter.KeyValue))
                            {
                                foreach (var e in dynamicAttachmentPoint.GetEntityTokens(null, null)) {
                                    yield return e;
                                }
                            }
                            continue;
                        }
                    }

                    foreach (EntityToken entityToken in attachmentPoint.GetEntityTokens(childEntityToken, dynamicContext))
                    {
                        yield return entityToken;
                    }
                }
            }
        }


        private AncestorMatch GetAncestorFromParentFilter(TreeNodeDynamicContext dynamicContext)
        {
            var dataNode = dynamicContext.CurrentTreeNode as DataElementsTreeNode;
            if(dataNode == null) return null;
            
            var parentIdFilter = dynamicContext.CurrentTreeNode.FilterNodes.OfType<ParentIdFilterNode>().FirstOrDefault();
            if (parentIdFilter == null) return null;

            Type ancestorType = parentIdFilter.ParentFilterType;
            object key = parentIdFilter.FindParentKeyValue(dynamicContext);

            return key == null ? null : new AncestorMatch { InterfaceType = ancestorType, KeyValue = key};
        }


        public override AncestorResult GetParentEntityToken(EntityToken childEntityToken, Type parentInterfaceOfInterest, TreeNodeDynamicContext dynamicContext)
        {            
            throw new NotImplementedException("Should never get called");            
        }


        protected override IEnumerable<Element> OnGetElements(EntityToken parentEntityToken, TreeNodeDynamicContext dynamicContext)
        {
            foreach (TreeNode childTreeNode in this.ChildNodes)
            {
                foreach (Element element in childTreeNode.GetElements(parentEntityToken, dynamicContext))
                {                    
                    element.ElementHandle.Piggyback[StringConstants.PiggybagTreeId] = this.Tree.TreeId;
                    
                    yield return element;
                }
            }
        }



        public override string ToString()
        {
            return "RootTreeNode, Id = " + this.Id;
        }
    }
}
